Palms of the past: Can morphometric phytolith analysis inform deep time evolution and palaeoecology of Arecaceae?

BACKGROUND AND AIMS

Palm fossils are often used as evidence for warm and wet palaeoenvironments, reflecting the affinities of most modern palms. However, several extant palm lineages tolerate cool and/or arid climates, making a clear understanding of the taxonomic composition of ancient palm communities important for reliable palaeoenvironmental inference. However, taxonomically identifiable palm fossils are rare and often confined to specific facies. Although the resolution of taxonomic information they provide remains unclear, phytoliths (microscopic silica bodies) provide a possible solution because of their high preservation potential under conditions where other plant fossils are scarce. We thus evaluate the taxonomic and palaeoenvironmental utility of palm phytoliths.

METHODS

We quantified phytolith morphology of 97 modern palm and other monocot species. Using this dataset, we tested the ability of five common discriminant methods to identify nine major palm clades. We then compiled a dataset of species' climate preferences and tested if they were correlated with phytolith morphology using a phylogenetic comparative approach. Finally, we reconstructed palm communities and palaeoenvironmental conditions at six fossil sites.

KEY RESULTS

Best performing models correctly identified phytoliths to their clade of origin only 59% of the time. Although palms were generally distinguished from non-palms, few palm clades were highly distinct, and phytolith morphology was weakly correlated with species' environmental preferences. Reconstructions at all fossil sites suggested that palm communities were dominated by Trachycarpeae and Areceae, with warm, equable climates, and high, potentially seasonal rainfall. However, fossil site reconstructions had high uncertainty and often conflicted with other climate proxies.

CONCLUSIONS

While phytolith morphology provides some distinction among palm clades, caution is warranted. Unlike prior spatially-restricted studies, our geographically and phylogenetically broad study indicates phytolith morphology may not reliably differentiate most palm taxa in deep time. Nevertheless, it reveals distinct clades, including some likely to be palaeoenvironmentally informative.

3D Cranial Nerve Imaging, a Novel MR Neurography Technique Using Black-Blood STIR TSE with a Pseudo Steady-State Sweep and Motion-Sensitized Driven Equilibrium Pulse for the Visualization of the Extraforaminal Cranial Nerve Branches

This study investigated the feasibility of a 3D black-blood STIR TSE sequence with a pseudo steady-state sweep and motion-sensitized driven equilibrium pulse for extraforaminal cranial nerve imaging on a 3T system. Assessments of healthy volunteers showed near-perfect agreement in nerve visualization with excellent to good visualization of the extraforaminal trigeminal, greater occipital, and facial nerves. Suppression of surrounding tissues was excellent to good. 3D cranial nerve imaging can produce nerve selective imaging of extraforaminal cranial and spinal nerve branches.

Salvage Transoral Laser Microsurgery for Radiorecurrent Laryngeal Cancer: Indications, Limits, and Outcomes

Purpose of Review

The aim of this report is to identify relevant literature reports on salvage transoral laser microsurgery (TLM); to consider its oncologic and functional outcomes, as well as reported complications; and to address indications and limitations of salvage TLM.

Findings

The weighted average of local control after first salvage TLM was 57%. Repeated TLM procedures for second or third recurrences were required in up to 41% of cases, resulting in a weighted average of local control with TLM alone of 67%. The rate of definite laryngeal preservation was 73%. The ultimate local control rate, including cases that required total laryngectomy, was 90%. The overall complication rate after salvage TLM was 14%.

Summary

Salvage TLM of radiorecurrent laryngeal cancer yields excellent oncologic outcomes. Serious complications are scarce, hospitalization times are short, and functional outcomes in terms of voice and swallowing are favorable when compared to open conservation laryngeal surgery. The key to success is an optimal patient selection.

Elevated carcinoembryonic antigen tumour marker caused by head and neck cancer: a case report and literature study

Carcinoembryonic antigen is a tumour marker commonly increased in gastrointestinal and pulmonary cancers. We report a case of a 46-year-old man with a mucoepidermoid carcinoma of the base of tongue with an elevated and traceable serum carcinoembryonic antigen level. This antigen proved to be a valuable marker in the treatment follow-up. When a raised carcinoembryonic antigen level is found, salivary gland malignancies should be taken into the differential diagnosis and clinical examination of the head and neck region should not be overlooked.

Long-term effects of cutting versus non-cutting instruments in FESS

BACKGROUND

Currently most ENT surgeons advocate using cutting instruments in Functional Endoscopic Sinus Surgery (FESS), based on the assumption of superior wound healing due to mucosal preservation. However, there is no scientific evidence of superiority of the cutting instruments.

METHODS

A prospective, randomized double blinded study was performed in 100 patients undergoing FESS, operated one side with non-cutting and the contra lateral side with cutting instruments. After a mean follow-up of 12 years after FESS, unilateral and global sino-nasal symptoms were scored by the patients using VAS, endoscopic abnormalities scored at both sides at the Outpatient clinic and radiologic abnormalities were described.

RESULTS

No significant differences between the sides operated by cutting and non-cutting instruments were found for sino-nasal symptomatic or for radiologic abnormalities between both sides. For the endoscopic parameters there was no difference for secretion or mucosa. Only for the presence of endoscopic synechiae there was a statistically significant difference between both groups. At the non-cutting side more synechiae were noticed, but no interference with sinus access, neither ventilation nor drainage was observed.

CONCLUSION

FESS performed with cutting instruments results in less synechiae formation compared to non-cutting instruments. However, the presence of synechiae is not associated with more symptoms or CT scan abnormalities.

Medullary thyroid cancer: prognostic factors for survival and recurrence, recommendations for the extent of lymph node dissection and for surgical therapy in recurrent disease

BACKGROUND

We reviewed our experience with MTC (medullary thyroid cancer), focusing on recurrence and survival, recommendations for the extent of lymph node (LN) dissection and surgery for recurrent disease.

METHODS

Of 51 MTC patients treated between 1988 and 2008 at the University Hospitals Leuven, 38 previously untreated patients were analysed.

RESULTS

Overall and disease-specific (DSS) five-year survival rates were 75% and 82%. Variables univariately associated with DSS were age, pN, stage, vascular invasion, pre-operative recurrent laryngeal nerve function and last calcitonin level. Recurrence occurred in 10 patients (26%). For recurrence, age was no longer a prognostic factor and post-operative calcitonin, number of positive LN and of positive compartments proved to be prognostic factors. Of 21 clinical NO patients, 2 out of 6 (33%) undergoing a prophylactic central neck dissection (ND) based on per-operative palpatory suspicion proved pN+, and 2 out of 9 patients (22%) undergoing a prophylactic lateral ND were pN+. Five patients surgically treated for recurrence did not achieve long-term normalisation of calcitonin, but remained alive with locoregional control.

CONCLUSION

Overall survival and DSS rates are within the range reported in the literature. The results confirm that (1) total thyroidectomy and central compartment dissection is the treatment of choice in the cN0 patients, (2) additional ipsilateral lateral ND is needed for cN+ disease in the ipsilateral lateral compartment, and (3) in the clinically uninvolved contralateral lateral neck, per-operative inspection should serve as a basis for a decision about further ND. Locoregional control and prolonged survival is achieved in surgically treated locoregionally recurrent MTC.

Malignant ectomesenchymoma of the paranasal sinuses with proptosis

PROBLEM

A 36-year-old woman presented with a feeling of pressure in the right orbit and proptosis of the right eye after a "common cold".

METHODOLOGY

Computed tomography (CT) of the maxillofacial region revealed, and endoscopy confirmed, a mass in the right ethmoid sinus, eroding the lamina papyracea and extending into the orbit. Pathology of multiple biopsies revealed a nasal neoplasm composed of neuroectodermal and mesenchymal neoplastic elements, suggestive of a malignant ectomesenchymoma (MEM). Magnetic resonance imaging was used for MEM staging. Computed tomography of the chest and abdomen show no evidence of distant metastases.

RESULTS

Due to the intracranial and intraorbital extension of the tumour, radical surgery was not an option. Appropriate chemotherapy (6 cycles of vincristine/ifosfamide/adriamycin and 2 cycles of vincristine/ifosfamide/cisplatin) and intensity-modulated radiation therapy were administered.

CONCLUSION

Twenty-eight months after treatment, there was no evidence of residual or metastatic disease.

A case series of embryonal rhabdomyosarcoma of the head and neck in adults

Embryonal rhabdomyosarcoma (RMS) is a rare malignant mesenchymal tumour that is believed to arise from cells committed to a skeletal muscle lineage. The head and neck region is among the most frequent locations for embryonal RMS in adults. We present a retrospective review of seven patients treated in our institution between 2000 and 2008. The age at diagnosis ranged from 19 to 41 years. One patient received primary surgery followed by adjuvant radiotherapy. Six inoperable patients were treated along a single chemotherapy protocol: the VIA-VIP regimen (a combination of vincristine, ifosfamide and doxorubicin (VIA) in alternation with etoposide, ifosfamide and cisplatin (VIP) administered in 3-weekly cycles), followed by local therapy, involving radiation therapy and/or surgery. An objective response to chemotherapy was observed in all six patients. Three out of seven patients remain disease-free with a median follow up of 4.5 years. Although the prognosis of head and neck embryonal RMS is worse in adults than in children, a multimodality treatment combining surgery, radiotherapy and intensive chemotherapy is feasible and effective in this population.

The black eyebrow sign in orbital blowout fracture

Orbital blowout fractures are frequently associated with intraorbital emphysema. This may be seen on a frontal skull radiograph as a lucent area at the superior side of the orbit, simulating a black eyebrow. Although computed tomography remains the primary imaging modality for assessing patients with clinically obvious blowout fracture, conventional radiography is often the first imaging study performed in cases of orbital trauma. By consequensce, knowledge of the black eyebrow sign is very useful especially to more unexperienced radiologists working at the emergency department.

Diffusion-weighted MRI in head and neck cancer

Diffusion-weighted MRI is an imaging technique showing molecular diffusion. Cell size, density and integrity influence the signal intensity seen on diffusion-weighted images. This technique is a helpful complementary tool to distinguish tumoral from non-tumoral tissue, and has several interesting applications in the evaluation of head and neck cancer.

Extension patterns of nasopharyngeal carcinoma

The nasopharynx represents an intersection between the nasal choanae, the oropharynx, the deep facial spaces, the skull base and the intracranial cavity. Most nasopharyngeal neoplasms are malignant tumors showing aggressive local infiltration along well-defined routes. The primary role of imaging is accurate tumor mapping and detection of possible tumor extension, especially to the skull base and the deep facial spaces. The aim of this paper is to illustrate these extension patterns of nasopharyngeal carcinomas on imaging and to show the particular implication of imaging in the correct staging of the lesion.

Evaluation of the larynx for tumour recurrence by diffusion-weighted MRI after radiotherapy: initial experience in four cases

Radiotherapy-induced changes in the soft tissues of the neck hamper the early detection of persistent or recurrent tumour by clinical examination and imaging procedures. Diffusion-weighted (DW) MRI is a non-invasive technique capable of probing tissue properties by measuring the movement of water. The purpose of the ongoing study is to examine the usefulness of DW-MRI for differentiation of persistent or recurrent tumour from post-radiotherapeutic sequelae or complications. Four patients, suspected of tumour recurrence after radiotherapy for laryngeal squamous cell carcinoma, were examined using a DW-MRI sequence on a clinical 1.5 T MR system prior to surgery. In two patients, the DW-MRI images showed an asymmetric hyperintense lesion on b1000 images with low apparent diffusion coefficient (ADC)-value, compatible with tumour on histopathology. All surrounding tissue presented high ADC values and absent signal on the b1000 images, histopathologically correlating to post-radiotherapeutic changes. The images of the third and fourth patient showed absent or minimal symmetric hyperintensity of the laryngeal soft tissues on the b1000 images and high ADC-values. In these cases, the histopathological diagnosis of radionecrosis was made and no tumour was found. In all four cases, differentiation of tumoral tissue from radiotherapy-induced tissue alterations was possible with DW-MRI.

Non-traumatic giant aneurysm of a superficial temporal artery

We present a case of giant aneurysm in the superficial temporal artery. A 59-year-old male was admitted to our hospital with a slowly growing swelling just in front of his right ear. Diagnosis was made by US and CT. CTA was able to provide accurate anatomic information and to eliminate the risks associated with diagnostic conventional angiography. A superselective embolization of the giant temporal aneurysm was performed.

Chronic maxillary atelectasis

Chronic maxillary atelectasis (CMA) is characterized by a reduced maxillary sinus volume due to an inward bowing of one or more of the sinus walls. The disorder is probably caused by an obstruction of the maxillary ostium, leading to a persistent negative pressure within the sinus lumen. To provide insight into the epidemiology, pathogenesis and treatment of this disorder, a retrospective study of twelve cases that met radiographic criteria of CMA was carried out. The patients were equally divided between both sexes and were on average 25 years old. Five of the twelve patients were under eighteen years of age. The patients had chronic sinonasal complaints except two, who had a "silent sinus syndrome", characterized by enophthalmos associated with a marked sinus deformation. This is the first report of CMA associated with a benign nasal tumour and also of CMA following cicatrisation due to nasal packing for bleeding after endoscopic sinus surgery. All patients were treated surgically by creating a middle meatal antrostomy, thus restoring sinus ventilation. To conclude, CMA is rare and probably underestimated, especially in the paediatric population. Different entities causing a complete ostial occlusion can lead to CMA. Endoscopically restoring maxillary sinus ventilation is the recommended treatment.

Boron biodistribution in Beagles after intravenous infusion of 4-dihydroxyborylphenylalanine–fructose complex

Boron biodistribution after intravenous infusion of 4-dihydroxyborylphenylalanine-fructose (BPA-F) complex was investigated in six dogs. Blood samples were evaluated during and following doses of 205 and 250 mg/kgbw BPA in a 30 min infusion, and 500 mg/kgbw in a 1h infusion. Samples from whole blood, urine, brain and other organs were analysed for boron content after varying times following the onset of infusion. The whole blood boron concentrations declined from 27 to 8.4 ppm over the period of 39-165 min after the onset of infusion and the levels increased from 1.9 to 12 ppm in the grey matter of the brain over the same period. The boron concentrations in whole blood decreased steadily, whereas the boron values in brain tissue rose steadily with time. It was concluded that whole blood boron concentrations do not seem to reflect accurately the boron concentration in brain tissue at respective time points.

Post-treatment imaging of head and neck cancer

The expected changes on CT or MRI after treatment of a head and neck cancer are described; it is important not to confuse such expected changes with persisting or recurrent tumour, or a treatment complication. Post-treatment CT or MRI is of value when a recurrent tumour is suspected, to confirm the presence of such a lesion and to determine its extent; this is important information for determining the possibility of salvage therapy. More rarely, imaging may be of use in the differentiation between tumour recurrence and a treatment complication. In patients with a high-risk profile for tumour recurrence after treatment, imaging is of value for surveillance of the patient, as an adjunct to clinical follow-up. The baseline study should be obtained about 3 to 4 months after the end of therapy. There is evidence that tumour recurrences can be detect earlier by systematic follow-up imaging.

Development of the orohypopharyngeal cavity in normal infants and young children

OBJECTIVE

To study the growth of the oropharynx and hypopharynx in infants and young children by measuring the lengths of the segments between nasopharyngeal valve and tongue base, tongue base and arytenoids, and arytenoids and upper esophageal sphincter. These measurements will be used as references for developing manofluoroscopy to study deglutition in infants and young children.

PATIENTS AND METHODS

Twenty-three children (14 boys, 9 girls) between birth and 4 years of age were prospectively studied. All children had near normal growth parameters and were free of medical illnesses or other major medical conditions that are known to influence the pharyngeal cavity. Lateral videofluoroscopy was used to assess the pharyngeal structures during breathing. All images were digitally recorded and analyzed using a computer program designed specifically for this study.

RESULTS AND CONCLUSIONS

Statistically significant correlations were found between the age or height of the patient and the distance from velopharyngeal valve to tongue base and the distance from tongue base to arytenoids, showing a linear increase of the length of the oro- and hypopharynx with age and patient height. There was no significant difference in the pharyngeal distances between boys and girls. On the basis of these results, a linear regression comparison could be established to define the length of each pharyngeal segment for any age until 4 years and for the 50th percentile of height.

Imaging of hypopharyngeal and cervical oesophageal cancer

Hypopharyngeal cancer, and particularly cervical oesophageal cancer, are infrequent tumours. Imaging methods assist in pre-treatment planning by better defining the extension of the lesions, by detecting subclinical neck adenopathies, as well as distant metastasis. In selected cases, imaging is also useful for treatment response assessment and surveillance.

BOLD contrast fMRI of whole rodent tumour during air or carbogen breathing using echo-planar imaging at 1.5 T

The aim of this study was to evaluate the feasibility of functional MR imaging (fMRI) at 1.5 T, exploiting blood oxygenation level-dependent (BOLD) contrast, for detecting changes in whole-tumour oxygenation induced by carbogen (5% CO2+95% O2) inhalation of the host. Adult WAG/Rij rats with rhabdomyosarcomas growing subcutaneously in the lower flank were imaged when tumours reached sizes between 1 and 11 cm3 (n=12). Air and carbogen were alternatively supplied at 2 l/min using a snout mask. Imaging was done on a 1.5-T MR scanner using a T2*-weighted gradient-echo, echo-planar imaging (GE-EPI) sequence. Analysis of the whole-tumour EPI images was based on statistical parametric maps. Voxels with and without signal intensity changes (SIC) were recorded. Significance thresholds were set at p<0.05, corrected for multiple comparisons. In continuous air breathing condition, 3 of 12 tumours showed significant negative SIC and 1 tumour had a clear-cut positive SIC. The remaining tumours showed very little or no change. When switching to carbogen breathing, the SIC were significantly positive in 10 of 12 tumours. Negative SIC were present in 4 tumours, of which three were simultaneously characterised by positive SIC. The overall analysis indicated that 6 of the 12 tumours could be considered as strong positive responders to carbogen. Our research demonstrates the applicability of fMRI GE-EPI at 1.5 T to study whole-tumour oxygenation non-invasively. The observed negative SIC during air condition may reflect the presence of transient hypoxia during these measurements. Selection of tumours on the basis of their individual response to carbogen is possible, indicating a role of such non-invasive measurements for using tailor-made treatments.

Lymph node metastases from head and neck squamous cell carcinoma: MR imaging with ultrasmall superparamagnetic iron oxide particles (Sinerem MR) -- results of a phase-III multicenter clinical trial

The aim of this study was to compare the clinical usefulness of ultrasmall superparamagnetic iron oxide (USPIO) MR contrast media (Sinerem, Guerbet Laboratories, Aulnay-sous-Bois, France) with precontrast MRI in the diagnosis of metastatic lymph nodes in patients with head and neck squamous cell carcinoma, using histology as gold standard. Eighty-one previously untreated patients were enrolled in a multicenter phase-III clinical trial. All patients had a noncontrast MR, a Sinerem MR, and surgery within a period of 15 days. The MR exams were analyzed both on site and by two independent radiologists (centralized readers). Correlation between histology and imaging was done per lymph node groups, and per individual lymph nodes when the short axis was > or = 10 mm. For individual lymph nodes, Sinerem MR showed a high sensitivity (> or = 88%) and specificity (> or = 77%). For lymph node groups, the sensitivity was > or = 59% and specificity > or = 81%. False-positive results were partially due to inflammatory nodes; false-negative results from the presence of undetected micrometastases. Errors of interpretation were also related to motion and/or susceptibility artifacts and problems of zone assignment. Sinerem MR had a negative predictive value (NPV) > or = 90% and a positive predictive value (PPV) > or = 51%. The specificity and PPV of Sinerem MR were better than those of precontrast MR. Precontrast MR showed an unexpectedly high sensitivity and NPV which were not increased with Sinerem MR. The potential contribution of Sinerem MR still remains limited by technical problems regarding motion and susceptibility artifacts and spatial resolution. It is also noteworthy that logistical problems, which could reduce the practical value of Sinerem MR, will be minimized in the future since Sinerem MR alone performed as good as the combination of precontrast and Sinerem MR.

Laryngeal squamous cell carcinoma presenting as a prelaryngeal neck abscess: report of two cases

Head and neck tumours presenting as a neck abscess are extremely rare. Two patients with laryngeal squamous cell carcinoma, presenting with a prelaryngeal abscess, are described. Although clinically and on the CT studies these cases were suspect for underlying malignancy, the initial biopsies were negative for cancer. Because of persistent suspicion, repeat biopsies finally confirmed the presence of a squamous cell carcinoma. Pathological examination after total laryngectomy showed cancer localised in one of the true vocal cords, invading the anterior commissure and thyroid cartilage. However, the prelaryngeal soft tissues were free of tumour, showing only inflammatory changes and collections of pus. These cases emphasize the importance of repeat targeted biopsies and follow-up CT-studies in patients with a prelaryngeal abscess of obscure aetiology, in order to exclude or confirm a possible underlying malignancy.

Absorbed doses from spiral CT and conventional spiral tomography: a phantom vs. cadaver study

For several radiological examinations, a clinician can select between conventional and spiral computed tomography. Using both techniques, this study aimed at evaluating the difference in absorbed doses when examining a single lateral jaw segment in a human cadaver head and Rando phantom. The present study involved the placement of thermoluminescent dosimeter (TLD) chips (GR-200) in the thyroid gland, and bilaterally, in the parotid and submandibular glands and the lenses of the eyes in both a human cadaver and a Rando phantom at corresponding locations. Consecutive conventional spiral tomographic examinations were carried out in both the left upper and lower premolar area, using a Cranex TOME multifunctional unit. Each examination consisted of 4 slices with a 2 mm slice thickness and exposure parameters of 57 kV, 56 seconds and 1.6-2.0 mA. Regarding spiral computed tomography (CT), a Somatom Plus S scanner (Siemens, Erlangen, Germany), with a slice thickness of 1 mm with settings at 120 kV and 165 mA, was used on both phantoms and separately in the upper and lower jaw. With conventional tomography, the findings of the present study showed that the parotid and submandibular glands on the side near the X-ray tube received the highest dose, both for the cadaver head (doses ranging from 0.5 to 1.3 mGy) and the phantom (doses ranging from 0.6 to 2.6 mGy). For CT of the upper jaw, the highest doses were delivered to the parotid glands with an average absorbed dose of 9.2 and 10.6 mGy for the cadaver head and phantom, respectively. The submandibular glands received the highest doses during CT examination of the lower jaw with an average of 7.8 and 12.9 mGy for the cadaver head and phantom, respectively. It appears from the present investigation that if small edentulous regions are examined, radiation doses during conventional tomography remain much lower than during CT imaging. However, when multiple tomographic cuts are required, a spiral CT examination can replace a series of conventional examinations, especially in cases such as the rehabilitation of an edentulous upper jaw or a more complex surgery.

Prefabrication of composite tissue for improved tracheal reconstruction

Tracheal repair tissues were evaluated experimentally to provide an evidence-based choice for decision-making in clinical tracheal reconstruction. Tracheal reconstructive tissue was characterized as providing for vascularization, support, and/or lining. A tissue equivalent was developed in the rabbit for each of the individual tissues. The individual tissues consisted of nonepithelialized soft tissue (vascularized fascia), epithelialized tissue (vascularized fascia grafted with buccal mucosa), and supportive tissue (ear cartilage). The 3 reconstructive tissues were evaluated in 30 rabbits after repair of an anterior laryngotracheal defect. Morphometric and histologic analysis was applied to the reconstructions. After a 1-month follow-up period, defects repaired with nonepithelialized soft tissue showed healing by secondary intention and a wound that was contracted to 44% of the initial surface area of the defect. Mucosa-lined soft tissue flaps and cartilage grafts showed a less than 10% wound contraction. Compared to cartilage grafts, mucosalined soft tissue (vascularized fascia grafted with buccal mucosa) seemed preferable for clinical use, because it showed healing by primary intention. A mucosa-lined radial forearm fascia flap was used successfully in cases of restenosis after tracheal resection. One deficiency of the mucosa-lined soft tissue was the absence of supportive tissue. In cases of extensive stenosis, it might be useful to obtain additional expansion of the airway lumen by creating a convexity at the site of reconstruction. In a second set of experiments, we attempted to improve the mucosa-lined soft tissue concept by adding elastic cartilage. A composite tissue consisting of vascularized fascia, buccal mucosa, and auricular cartilage was developed. Heterotopic prefabrication of the composite tissue was essential for survival of the cartilaginous component. Additional airway lumen expansion could be obtained after heterotopic flap prefabrication. After experimental evaluation, the concept of the prefabricated composite tissue was successfully applied in a clinical case of long-segment stenosis. Experimental and clinical evidence suggests that the combination of buccal mucosa and fascia form an optimized tissue combination for tracheal reconstruction. This combination can be improved by adding strips of autologous ear cartilage.

The relation of CT-determined tumor parameters and local and regional outcome of tonsillar cancer after definitive radiation treatment

PURPOSE

To investigate the value of CT-derived tumor parameters as predictor of local and regional outcome of tonsillar squamous cell carcinoma treated by definitive radiation therapy.

METHODS AND MATERIALS

The pretreatment CT studies of 112 patients with tonsillar squamous cell carcinoma were reviewed. After redigitizing the films, primary and nodal tumor volume was calculated with the summation-of-areas technique. The nodal CT aspect was graded using a 3-point scale (homogenous, inhomogeneous, and necrotic). Mean follow-up time was 33 months. Actuarial statistical analysis of local and regional outcome was done for each of the covariates; multivariate analysis was performed using Cox's proportional hazards model.

RESULTS

In the actuarial analysis, CT-determined primary tumor volume was significantly correlated with local recurrence rate (p < 0.05) when all patients were considered, but primary tumor volume did not predict local control within the T2, T3, and T4 category. CT-determined nodal volume was significantly related to regional outcome (p < 0.01), but nodal density was not. Total tumor volume was not significantly related to locoregional outcome (p = 0.1). In the multivariate analysis, the T and N categories were the independent predictors of local and regional outcomes, respectively.

CONCLUSION

Compared to other head-and-neck sites, primary and nodal tumor volume have only marginal predictive value regarding local and regional outcome after radiation therapy in tonsillar cancer.

Sinochoanal polyp and its variant, the angiomatous polyp: MRI findings

The angiomatous polyp corresponds to the vascular compromised nasochoanal part of a sinochoanal polyp. We describe the MRI characteristics of such lesions in four patients. All patients had an angiomatous polyp, in three cases as part of an antrochoanal polyp, and in one case as part of a sphenochoanal polyp. The unenhanced MR images depicted the typical appearance of a sinochoanal polyp, hypointense on T1-weighted and hyperintense on T2-weighted images. On gadolinium-enhanced MR images, the sinusal part showed little or no peripheral enhancement; however, the nasochoanal part, corresponding to the angiomatous polyp, showed strong enhancement. An angiomatous polyp mimics a hypervascular mass lesion on enhanced MR studies. The anatomic location and association with a sinusal polyp allows the correct diagnosis.

The utility of SPECT in determining the relationship between radiation dose and salivary gland dysfunction after radiotherapy

Salivary gland scintigraphy (SGS) is used to depict salivary gland dysfunction after radiotherapy (RT). The aim of this study was to investigate the utility of SGS combined with single photon emission computed tomography (SPECT). Twenty-one patients with a carcinoma of head and neck underwent SGS before and 1 month after RT. After injection of 370 MBq 99Tcm-pertechnetate, a biplanar dynamic acquisition (12 x 1 min) was started, followed by a SPECT acquisition during 4 min. Carbachol was then injected and a second dynamic study (16 x 1 min) was performed, again followed by a SPECT acquisition. The salivary excretion fraction (SEF) was calculated both from the geometric mean planar image for each parotid and from the SPECT data for each transverse plane through the parotids. The RT-induced changes in the SEF (dSEF) were correlated with the mean radiation dose calculated using tomography-based dosimetry. The mean radiation dose to the parotids was 44 Gy (range 4.4-68.1 Gy). The mean range of the variation in radiation dose to the transverse slices within the parotids of a patient was 24 Gy (range 6.2-51.9 Gy). Considering all transverse planes through the parotids in all patients, a linear correlation was found between the dSEF calculated using SGS-SPECT and the radiation dose (r=0.45, P=0.0001). Thirteen patients had a variation in radiation dose within the parotids of more than 20 Gy. In nine of these a significant intra-individual correlation between radiation dose and the dSEF of the transverse parotid slices was found (r range 0.55-0.97; P value range 0.037-0.0001). In conclusion, SGS-SPECT can be used for monitoring radiation-induced parotid gland dysfunction. It offers the unique possibility for the assessment of intra-individual dose-dysfunction curves in patients with large variations in the radiation dose within the parotids.

Results of larynx preservation surgery for advanced laryngeal cancer through tracheal autotransplantation

OBJECTIVE

To evaluate the use of tracheal autotransplantation for reconstruction of the hemilaryngectomy defect that includes the hemicricoid cartilage and results from resection of laryngeal or hypopharyngeal cancer.

DESIGN

The clinical records of 28 patients undergoing primary or salvage hemicrico-hemilaryngectomy for laryngeal (26 patients) and pyriform sinus (2 patients) cancer were analyzed for function and local control.

SETTING

Academic center.

PATIENTS

Case series review of 28 consecutive patients treated during a 3(1/2)-year period who had an average follow-up period of 19 months.

INTERVENTION

Twenty-five men and 3 women, aged from 28 to 79 years, underwent a hemilaryngectomy that included the hemicricoid cartilage, the ipsilateral thyroid lobe, and a unilateral or bilateral lymph node dissection. In 26 patients, these extensive defects were reconstructed with a tracheal autotransplantation that restored the larynx at the glottic and subglottic levels. In 2 patients, the defect was converted into a total laryngectomy because of tumor extension beyond the resection margins of a hemicrico-hemilaryngectomy.

MAIN OUTCOME MEASURES

The times to decannulation and retake of full oral feeding, the quality of speech, and the incidence and site of recurrent cancer were assessed.

RESULTS

Of the 26 patients undergoing tracheal autotransplantation, 24 were decannulated and all regained the ability to maintain nutrition by mouth. Ultimate voice quality was "subnormal" to "moderately hoarse" in all patients. Five recurrences developed of which 2 were treated with total laryngectomy.

CONCLUSIONS

Functional reconstruction of extensive laryngeal defects can be achieved with an autotransplantation of cervical trachea, with favorable functional results and acceptable morbidity. This technique expands the limits of conservation surgery for selected laryngeal and hypopharyngeal tumors.

The accuracy of spiral tomography to assess bone quantity for the preoperative planning of implants in the posterior maxilla

When planning to place implants in the posterior region of the maxilla, the location of the maxillary sinus floor is influencing the available bone height and the implant length chosen. The aim of the present study was to evaluate in vitro the spiral tomographic technique that could be used for pre-operative implant planning. Tomographs were taken of 6 dry human skulls using the Cranex Tome multifunctional unit (Orion Corporation Soredex, Helsinki, Finland). Three sites were selected in the left posterior maxilla and marked with gutta percha meaning a total of 18 sites (6 x 3 = 18) for interpretation. Bone height and width were measured on the tomographs and after sectioning also on the skulls. The values obtained from the measurements on tomographs were divided by an enlargement factor of 1.5 (as defined by the manufacturer) and then compared with those from the real measurements on the skulls. Real measurements were on average 0.24 mm (SD 0.19) lower than the tomographic measurements (P < 0.05). From the present results it could be concluded that spiral tomography using the recently developed Cranex Tome reveals sufficient information and detail for pre-operative planning of a limited edentulous region.

Laryngeal or hypopharyngeal squamous cell carcinoma: can follow-up CT after definitive radiation therapy be used to detect local failure earlier than clinical examination alone?

PURPOSE

To determine if follow-up computed tomography (CT) after definitive radiation therapy for laryngeal or hypopharyngeal (laryngopharyngeal) carcinoma allows the detection of local failure earlier than clinical examination alone.

MATERIALS AND METHODS

Pre- and post-radiation therapy follow-up CT scans in 66 patients were reviewed retrospectively. All patients underwent definitive hyperfractionated radiation therapy and were followed up clinically for at least 2 years after its completion. Post-radiation therapy CT scans (N = 153) were evaluated for posttreatment changes with a three-point score: A score of 1 represented expected posttreatment changes; 2, focal mass with a maximal diameter of less than 1 cm and/or asymmetric obliteration of laryngeal tissue planes; or 3, focal mass with a maximal diameter equal to or greater than 1 cm or estimated tumor volume reduction of less than 50%. All patients underwent the first posttreatment CT study 1-6 months after therapy. New or progressive laryngeal cartilage changes were noted. The clinical impression of the larynx at the time of each follow-up CT scan was also recorded.

RESULTS

In 12 of 29 (41%) patients with treatment failure at the primary site, follow-up CT scans were definite for local failure (score, 3) a mean of 5.5 months (median, 3.5 months; range, 1-17 months) before clinical examination results.

CONCLUSION

In many patients, follow-up CT shows local failure earlier than does clinical examination alone.

Progress in larynx-sparing surgery for glottic cancer through tracheal transplantation

The current surgical treatment for unilateral, advanced glottic cancer is a total laryngectomy. Usually, the noninvolved hemilarynx needs resection because the resulting laryngeal defect cannot be reconstructed after adequate tumor resection. Experimental findings suggest that segments of autologous trachea may restore extended laryngeal defects. The authors used tracheal transplantation to save laryngeal function after the removal of advanced glottic cancer. In this case series review, 10 patients were treated during a 1.5-year period, with an average follow-up of 8 months. Evaluated factors included survival of the tracheal transplant and functional outcome with regard to the onset and quality of the airway, speech, and deglutition. The authors showed that segments of cervical trachea may restore extended laryngeal defects after initial revascularization by a radial forearm fascial flap. The fascial flap served as a vascular carrier for the transplanted trachea. Follow-up showed the stability of the reconstruction. Compared with a total laryngectomy, a striking improvement in patient comfort and function was noticed. Transplantation of the trachea is a technique that may save laryngeal function after the treatment of advanced-stage glottic cancer. These findings may improve laryngeal preservation strategies in treating laryngeal cancer.

Tumoural perfusion as measured by dynamic computed tomography in head and neck carcinoma

PURPOSE

To investigate the intra- and interobserver variability, as well as the intra- and interpatient variability of CT-determined tumour perfusion in head and neck tumours, and to evaluate the preliminary value of this parameter as predictive factor of local failure after treatment by definitive radiotherapy.

MATERIALS AND METHODS

In 41 patients the perfusion of a primary head and neck squamous cell carcinoma was estimated using dynamic CT. A 40-ml intravenous bolus of a low-osmolar non-ionic contrast agent was rapidly injected over 5 s (8 ml/s), while a dynamic acquisition of image data was obtained during the first pass at the level of the largest axial tumour surface. A time-density curve was constructed for the primary tumour and the carotid artery. The perfusion in the selected tumour region of interest was calculated by dividing the slope of the tumour-time density curve by the maximal value in arterial density. Tumour volume was calculated on the CT-images and correlated with perfusion rate.

RESULTS

The mean perfusion rate was 86.4 ml/min per 100 g (median, 80.6; SD, 43.05; range, 31.7-239.8 ml/min per 100 g). No systematic difference was found between the measurements performed by two independent observers. The intratumoural COV was 0.22, the intertumoural COV 0.37. No correlation was found with tumour volume. Ten out of 20 patients with a perfusion rate < 80 ml/min per 100 g were not locally controlled, while nine out of 21 patients with a value > 80 ml/min per 100 g did show a local failure (P = 0.19).

CONCLUSIONS

CT-determined perfusion measurements of head and neck tumours are feasible. No correlation with tumour volume and a sufficiently large COV were found to consider this parameter as a possible prognostic factor for outcome after radiotherapy. More patients need to be investigated to test the hypothesis that tumours with a low CT determined perfusion rate have a higher risk of local failure.

Imaging of the parapharyngeal space

The parapharyngeal space is a deep space of the neck, always well visible on CT and MR imaging of the head and neck; in normal circumstances, this space should look symmetrical. The parapharyngeal space is often subdivided in compartments; such subdivision is helpful when considering the site of origin of a parapharyngeal space mass. Several concepts of compartmentalization of this space exist, sometimes leading to confusion; not the names but the anatomy is important to know. This manuscript reviews shortly the anatomy of the parapharyngeal space, the use of modern cross-sectional imaging methods in the evaluation of this region, and focuses somewhat more on imaging of primary parapharyngeal lesions.